Question

Which of the following is not an olfactory indicator ?

• A. Clove oil
• B. Vanilla
• C. Sweet potato
• D. All of these

Hint:

Common olfactory indicators include onion, vanilla extract, and clove oil. Remember that their key feature is a change in smell in response to pH changes.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
An olfactory indicator is a substance whose smell (odor) changes depending on whether it is mixed with an acidic or a basic solution. They are used to identify the nature of a solution when a visual indicator is not suitable.

Step 2: Detailed Explanation:
\[\begin{array}{rl} \bullet & \text{Clove oil: Has a characteristic smell. It loses its smell in a basic solution but retains it in an acidic solution. Thus, it is an olfactory indicator. } \\ \bullet & \text{Vanilla extract: Has a pleasant smell which is retained in an acidic solution but vanishes in a basic solution. Thus, it is an olfactory indicator. } \\ \bullet & \text{Sweet potato: Is a vegetable. It does not have a characteristic strong odor that changes predictably in acidic or basic media. Therefore, it cannot be used as an olfactory indicator. } \\ \end{array}\]

Step 3: Final Answer:
Sweet potato is not an olfactory indicator.